In the heretofore used welding apparatuses for welding base pins of a fluorescent lamp and lead wires inserted into the base pins, it has been the general practice to move the fluorescent lamp stepwise by a transfer device to a predetermined station (welding station) where a pair of base pins of the fluorescent lamp are welded by a pair of capacitor discharging arc welding electrodes. However, the conventional apparatus had a disadvantage that in repeated welding of the pins, the tips of the welding electrodes were so contaminated and deformed by the welding sputter and arc that it was necessary to frequently stop the welding operation to clean and reshape the welding electrodes, resulting in a considerable reduction in the rate of operation of the base pin welding apparatus and adverse affects on the entire system in operative association therewith.